JP2016069425A - Additive for lubricant and lubricant composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaner for lubricant capable of increasing basic value without increasing ash content, and capable of increasing high temperature stability and basic value holding property.SOLUTION: There is provided an additive for lubricant represented by the following general formula (1), where Yto Yare each independently a hydrogen atom or a substituent, at least one of them is R or OR, and R is a substituted or unsubstituted aliphatic hydrocarbon group having 10 to 25 carbon atoms.SELECTED DRAWING: None

Description

  The present invention relates to a lubricating additive used in a lubricating oil and a lubricating oil composition using the additive, for example, a lubricating additive and a lubricating oil composition used for an internal combustion engine.

Conventionally, in an internal combustion engine lubricating oil, a metallic detergent and an ashless dispersant are used in combination as a detergent dispersant. As metal-based detergents, alkali metal or alkaline earth metal sulfonates, phenates, salicylates, phosphonates, and overbased products thereof are generally used.
In engines, environmental pollution countermeasures such as nitrogen oxides (NOx) and particulate matter (hereinafter also referred to as “PM”) in exhaust gas are important issues, and nitrogen oxidation in exhaust gas is an important issue. Waste and particulate emissions are urgently needed. As these measures, NOx reduction is dealt with by increasing exhaust gas recirculation (EGR) or lowering the combustion peak temperature by delaying the fuel injection timing.

  However, since lowering the combustion peak temperature leads to an increase in black smoke and PM, it is necessary to install an exhaust gas aftertreatment device. Although PM traps or oxidation catalysts are being studied for this exhaust gas aftertreatment device, all of them have a filter-like structure, so that conventional engine oils are clogged (clogged) with metal in the oil. Is a problem.

Therefore, in order to improve cleanliness while reducing the metal content in the lubricating oil, attempts have been made to improve cleanliness and base number maintenance with ashless additives. For example, Patent Document 1 shows that by using an amino alcohol having a specific structure as an additive for lubricating oil, it is possible to improve the cleanliness of the lubricating oil and reduce the use of a metallic detergent. .
Patent Document 2 discloses that the cleanliness and base number maintainability can be enhanced by a specific benzimidazole-based, imidazole-based, or tetrazole-based compound.

JP 07-316576 A Japanese Patent No. 5400612

However, the additives of Patent Documents 1 and 2 are not sufficient in the effect of suppressing oxidative deterioration under high temperature environments and the base number maintenance property, and further improvements are desired.
The present invention has been made in view of the above problems, and an object of the present invention is to suppress oxidative degradation in a high temperature environment of, for example, 270 ° C. or higher without generating lacquer (sediment). Another object of the present invention is to provide an ashless detergent capable of improving the base number maintenance performance.

（ただし、Ｙ¹〜Ｙ⁴はそれぞれ独立に水素原子又は置換基であり、これらのうち少なくとも１つはＲ又はＯＲのいずれかであり、Ｒは、置換若しくは無置換の炭素数１０〜２５の脂肪族炭化水素基である。）
［２］基油に、上記［１］に記載の潤滑油用添加剤を配合してなる潤滑油組成物。 As a result of intensive studies, the present inventors have found that the above-mentioned problems can be solved by a pyrazole compound into which a substituent having a specific structure is introduced, and have completed the present invention described below.
[1] An additive for lubricating oil represented by the following general formula (1).

(However, Y < ¹ > -Y < ⁴ > is a hydrogen atom or a substituent each independently, and at least 1 is either R or OR among these, R is a substituted or unsubstituted C10-25 carbon number. It is an aliphatic hydrocarbon group.)
[2] A lubricating oil composition comprising the base oil blended with the additive for lubricating oil according to the above [1].

  According to the present invention, it is possible to provide an ashless detergent that does not generate lacquer (sediment) and suppresses oxidative degradation and improves base number maintenance performance, for example, in a high temperature environment of 270 ° C. or higher. .

Hereinafter, the present invention will be described in more detail.
<Additive for lubricating oil>
The additive for lubricating oil according to the embodiment of the present invention is represented by the following general formula (1).

In the general formula (1), Y ^{1 to} Y ⁴ are each independently a hydrogen atom or a substituent, and at least one of them is either R or OR, and R in R or OR (simply “R”) Is also a substituted or unsubstituted aliphatic hydrocarbon group having 10 to 25 carbon atoms.
The lubricant additive of the present embodiment increases the base number while improving the oil solubility in the lubricant base oil by bonding a substituent (R or OR) having a predetermined number of carbon atoms to the pyrazole skeleton. In addition, it is possible to improve the high-temperature stability and the base number maintenance of the lubricating oil composition, and it can be suitably used as a detergent. Moreover, since the said additive does not contain a metal part, it does not generate lacquer.
Here, the carbon number of R is preferably 12 to 24 from the viewpoint of improving the base solubility and the base number while also improving the oil solubility in the lubricating base oil. More preferably.
In addition, in this embodiment, 1 type selected from the compound shown by the said General formula (1) may be used, and 2 or more types may be used in combination.

The substituted or unsubstituted aliphatic hydrocarbon group represented by R may be either saturated or unsaturated, may be linear or branched, and may have a cyclic structure. Specific examples of the substituted or unsubstituted aliphatic hydrocarbon group include a substituted or unsubstituted alkyl group and a substituted or unsubstituted alkenyl group, and a substituted or unsubstituted alkyl group is more preferable.
Examples of the substituent include a hydroxyl group a thiol group (-SH), and a substituted group selected from a halogen atom, and an amino group (-NH _2), hydroxyl Among these, preferred. Therefore, as the substituted aliphatic hydrocarbon group, a hydroxyalkyl group and a hydroxyalkenyl group are more preferable, and a hydroxyalkyl group is more preferable.

  More specifically, the unsubstituted aliphatic hydrocarbon group used for R is decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, octadecyl, nonadecyl, icosyl. Group, heicosyl group, docosyl group, tricosyl group, tetracosyl group, pentacosyl group, etc., an alkyl group having 10 to 25 carbon atoms; decenyl group, undecenyl group, dodecenyl group, tridecenyl group, tetradecenyl group, pentadecenyl, hexadecenyl group, heptadecenyl group, C10-25 alkenyl groups such as octadecenyl group, nonadecenyl group, eicosenyl group, heicosenyl group, dococenyl group, tricocenyl group, tetracocenyl group, pentacocenyl group, etc., may be mentioned, these may be linear or branched Even if it becomes Stone, it may become to have a cyclic structure. Moreover, as an example of a more specific alkyl group, n-dodecyl group, n-octadecyl group, n-nonadecyl group, etc. are mentioned.

More specifically, the aliphatic hydrocarbon group substituted with a hydroxyl group in R is more specifically a hydroxydecyl group, a hydroxyundecyl group, a hydroxydodecyl group, a hydroxytridecyl group, a hydroxytetradecyl group, or a hydroxypentadecyl group. , Hydroxyhexadecyl group, hydroxyheptadecyl group, hydroxyoctadecyl group, hydroxynonadecyl group, hydroxyicosyl group, hydroxyhenicosyl group, hydroxydocosyl group, hydroxytricosyl group, hydroxytetracosyl group, hydroxypentacosyl group A hydroxyalkyl group having 10 to 25 carbon atoms such as syl group; hydroxydecenyl group, hydroxyundecenyl group, hydroxydodecenyl group, hydroxytridecenyl group, hydroxytetradecenyl group, hydroxypentadecenyl Nil, hydro Cihexadecenyl, hydroxyheptadecenyl, hydroxyoctadecenyl, hydroxynanodecenyl, hydroxyeicosenyl, hydroxyhenicosenyl, hydroxydocosenyl, hydroxytricocenyl, hydroxytetra Examples thereof include hydroxyalkenyl groups having 10 to 25 carbon atoms such as a cocenyl group and a hydroxypentacocenyl group. These may be linear, may be branched, or may have a cyclic structure, but are preferably linear. Furthermore, the position of the hydroxyl group may be any.
Moreover, it is preferable that the hydroxyalkyl group used as R is a substituent represented by the following general formula (1-A).

ただし、一般式（１−Ａ）において、ｍは０〜２４の整数を表し、Ｒ²¹は水素原子又は炭素数１〜２４のアルキル基であり、*は結合位置であることを示す。なお、一般式（１−Ａ）においては、ｍが１又は２であるとともに、Ｒ²¹が炭素数５〜２３のアルキル基であることが好ましく、ｍが１であるとともに、Ｒ²¹は炭素数８〜１８のアルキル基であることがより好ましい。ここで、アルキル基は、直鎖状であってもよいし、分岐状であってもよいし、環状構造を有していてもよいが、直鎖状であることが好ましい。
この一般式（１−Ａ）で示されるヒドロキシアルキル基の具体的な例としては、２−ヒドロキシ−ｎ−テトラデシル基、２−ヒドロキシ−ｎ−ヘキサデシル基、３−ヒドロキシ−ｎ−ヘプタデシル基等が挙げられる。

In General Formula (1-A), m represents an integer of 0 to 24, R ²¹ represents a hydrogen atom or an alkyl group having 1 to 24 carbon atoms, and * represents a bonding position. In general formula (1-A), m is 1 or 2, R ²¹ is preferably an alkyl group having 5 to 23 carbon atoms, m is 1, and R ²¹ is carbon number. More preferably, it is an 8-18 alkyl group. Here, the alkyl group may be linear or branched, or may have a cyclic structure, but is preferably linear.
Specific examples of the hydroxyalkyl group represented by the general formula (1-A) include 2-hydroxy-n-tetradecyl group, 2-hydroxy-n-hexadecyl group, 3-hydroxy-n-heptadecyl group and the like. Can be mentioned.

Moreover, it is more preferable that R or OR used for Y ^{1 to} Y ⁴ contains an oxygen atom, that is, at least one of Y ^{1 to} Y ⁴ is a hydroxyalkyl group having 10 to 25 carbon atoms, Or it is more preferable that it is a C10-C25 alkoxyl group. When R or OR used for Y ^{1 to} Y ⁴ contains an oxygen atom, high-temperature stability, base number maintenance, and the like are easily improved.
Furthermore, when at least one of Y ^{1 to} Y ⁴ is OR, Y ² is preferably OR from the viewpoint of ease of production.

As described above, at least one of Y ¹ to Y ⁴ is R or OR described above, while the other substituents used for Y ¹ to Y ⁴ (hereinafter referred to as substituent (X)). Is not particularly limited, specifically, a hydrocarbon group having 1 to 9 carbon atoms which may have at least one of a nitrogen atom, an oxygen atom, a sulfur atom, and a halogen atom, substituted or unsubstituted And a hydrocarbon oxy group having 1 to 9 carbon atoms, a hydrocarbon group having 6 to 12 carbon atoms containing an aromatic ring, a hydroxyl group, a thiol group, a halogen atom, and an amino group. Here, examples of the halogen atom include a chlorine atom, a bromine atom, and an iodine atom, and a chlorine atom is preferable.

  Moreover, as a C1-C9 hydrocarbon group which may have at least one of a nitrogen atom, an oxygen atom, a sulfur atom, and a halogen atom, a substituted or unsubstituted hydrocarbon group, an ether bond (-O The hydrocarbon group which has either-), an ester bond (-COO-), and a thioether bond (-S-) is mentioned.

Examples of the substituted or unsubstituted hydrocarbon group used for the substituent (X) include an unsubstituted aliphatic hydrocarbon group and a substituted aliphatic hydrocarbon group.
The unsubstituted aliphatic hydrocarbon group may be either saturated or unsaturated. Specifically, an alkyl group or an alkenyl group is preferable, and among these, an alkyl group is more preferable. The unsubstituted aliphatic hydrocarbon group may be linear or branched, and may have a cyclic structure.
Examples of the substituted aliphatic hydrocarbon group include an aliphatic hydrocarbon group substituted with a substituent selected from a hydroxyl group, a thiol group, an amino group, and a halogen atom. Among these, an aliphatic hydrocarbon group substituted with a hydroxyl group is preferable, a hydroxyalkyl group and a hydroxyalkenyl group are more preferable, and a hydroxyalkyl group is more preferable. The substituted aliphatic hydrocarbon group may be linear or branched, and may have a cyclic structure.

  In addition, a hydrocarbon group having any one of an ether bond (—O—), an ester bond (—COO—), and a thioether bond (—S—) is an ether bond (—O—), an ester bond (—COO—). ), And an aliphatic hydrocarbon group having any of thioether bonds (—S—), and are represented by the following formulas (1-1), (1-2), and (1-3). A specific example is given.

In the general formulas (1-1), (1-2), and (1-3), R ¹¹ , R ¹³ , and R ¹⁵ are each a divalent aliphatic hydrocarbon group, and R ¹² , R ¹⁴ , R ¹⁶ are each a monovalent aliphatic hydrocarbon group, and * represents a bonding position. Similarly, the general formula (1-1) or (1-3), the total number of carbon atoms of R ¹¹ and R ^12, and the total number of carbon atoms of R ¹⁵ and R ¹⁶ are each a 2-9. In the general formula (1-2), the total number of carbon atoms of R ¹³ and R ¹⁴ is 2-8.
R ¹¹ , R ¹³ and R ¹⁵ are preferably alkylene groups, and the alkylene groups may be linear or branched or have a cyclic structure. R ¹² , R ¹⁴ , and R ¹⁶ are preferably alkyl groups, and the alkyl groups may be linear or branched or have a cyclic structure.

Examples of the substituted or unsubstituted hydrocarbon oxy group having 1 to 9 carbon atoms used for the substituent (X) include an alkoxy group, an alkenyloxy group, and a hydroxyl group, a thiol group, a halogen atom, and an amino group. Examples include those in which the selected substituent is substituted.
As a C6-C12 hydrocarbon group containing an aromatic ring used for substituent (X), an aryl group and an aralkyl group are mentioned. As an aryl group, you may have substituents, such as a halogen atom and an alkyl group, and a phenyl group, a chlorophenyl group, a naphthyl group, a tolyl group, a biphenylyl group etc. are mentioned specifically ,. Examples of the aralkyl group include benzyl group and phenethyl group.

In addition, it is preferable that at least one of Y ^{1 to} Y ⁴ is selected from an aryl group having 6 to 12 carbon atoms. In addition, it is also preferable that at least one of Y ^{1 to} Y ⁴ is selected from an alkyl group having 1 to 4 carbon atoms.
Here, the aryl group having 6 to 12 carbon atoms may be either substituted or unsubstituted, and specific examples include a phenyl group, a chlorophenyl group, a naphthyl group, a tolyl group, an ethylphenyl group, and a biphenylyl group. An aryl group having 6 to 9 carbon atoms is preferred, and a phenyl group is more preferred. The aryl group having 6 to 12 carbon atoms is preferably substituted with Y ¹ .
Examples of the alkyl group having 1 to 4 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, and tert-butyl group. Of these, a methyl group is preferred.
Furthermore, in one embodiment of the present invention, it is preferred that Y ⁴ is an alkyl group having 1 to 4 carbon atoms, and more preferably Y ⁴ is a methyl group. Further, even more preferably none of Y ² and Y ⁴ is an alkyl group having 1 to 4 carbon atoms, base number retention properties, both from the viewpoint of enhancing the high temperature stability of Y ² and Y ⁴ is a methyl group Even more preferably.

In addition, at least one of Y ^{1 to} Y ⁴ is preferably a hydrogen atom or a hydroxyl group, but more preferably a hydrogen atom. When at least one of Y ^{1 to} Y ⁴ is a hydrogen atom, either Y ¹ or Y ³ is preferably a hydrogen atom, and Y ³ is a hydrogen atom from the viewpoint of improving base number maintenance and high-temperature stability. It is more preferable that
When at least one of Y ^{1 to} Y ⁴ is a hydroxyl group, Y ² is preferably a hydroxyl group from the viewpoint of ease of production. In addition, when Y ² is a hydroxyl group, the compound represented by the general formula (1) is represented by the following formula (2-A). However, this compound exhibits tautomerism and is represented by the formula (2-B). It becomes an equilibrium state that coexists with the isomer. Therefore, in this specification, these tautomers are all included in the compound represented by the general formula (1).

Moreover, in General formula (1), it is preferable that any ^one of Y < ¹ > -Y < ⁴ > is above-described R or OR, and other three are substituents (X) or a hydrogen atom.
In this case, the other three of Y ^{1 to} Y ⁴ are each independently selected from an alkyl group having 1 to 4 carbon atoms, a hydrogen atom, a hydroxyl group, and an aryl group having 6 to 12 carbon atoms. It is more preferable.
Two of Y ¹ to Y ⁴ other than R or OR are selected from an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms, and the other one is a hydrogen atom or a hydroxyl group. More preferably, three Y ¹ to Y ⁴ other than R or OR are selected from an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms.
In the general formula (1), any ^one of Y ^{1 to} Y ⁴ is R or OR described above, and the other three are other examples. The following general formulas (2-1) to (2- Among these, the compound represented by the general formula (2-1) or (2-3) is preferable, and the compound represented by the general formula (2-3) is more preferable.

上記各一般式（２−１）〜（２−５）において、Ｒ及びＹ¹〜Ｙ⁴は上記したとおりである。

In each of the general formulas (2-1) to (2-5), R and Y ^{1 to} Y ⁴ are as described above.

In general formula (1), it is also preferred that two of Y ^{1 to} Y ⁴ are R or OR as described above, and the other two are the other. In this case, the other two of Y ^{1 to} Y ⁴ are as described above, but each independently from an alkyl group having 1 to 4 carbon atoms, a hydrogen atom, a hydroxyl group, and an aryl group having 6 to 12 carbon atoms. More preferably, it is selected.
One of the other two of Y ^{1 to} Y ⁴ is selected from an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms, and the other is selected from a hydrogen atom. More preferably, one is an alkyl group having 1 to 4 carbon atoms, and the other is more preferably a hydrogen atom.
Furthermore, specific examples in the case where two of Y ^{1 to} Y ⁴ in the general formula (1) are R or OR described above are represented by the following general formula (2-6) or general formula (2-7). Can be mentioned.

一般式（２−６）において、Ｙ³、Ｙ⁴及びＲは上記と同じであるとともに、Ｒは互いに同一であってもよいし、異なっていてもよい。同様に、一般式（２−７）において、Ｙ²、Ｙ³及びＲは上記と同じであるとともに、Ｒは互いに同一であってもよいし、異なっていてもよい。なお、一般式（２−１）〜（２−７）から選択される２種以上が混合されて使用されてもよい。

In General Formula (2-6), Y ³ , Y ⁴ and R are the same as described above, and R may be the same as or different from each other. Similarly, in the general formula (2-7), Y ² , Y ³ and R are the same as described above, and R may be the same as or different from each other. In addition, 2 or more types selected from general formula (2-1)-(2-7) may be mixed and used.

  In addition, manufacture of the additive for lubricating oil is performed under a catalyst as needed as mentioned later, and various impurities other than the target compound may be produced in the reaction process. Furthermore, the raw material may contain various impurities. For this reason, the additive for lubricating oil may contain catalyst residues and various impurities other than the target compound, and those containing catalyst residues and various impurities in addition to the target compound as described above may also be used as the lubricant of the present invention. Included in oil additives.

<Method for producing additive for lubricating oil>
The additive for lubricating oil according to the present embodiment includes, for example, a compound (A1) having a pyrazole skeleton or a pyrazolone skeleton, and a compound (B1) having a group corresponding to R or a group constituting a part of R. Can be obtained by reacting.
Here, the compound (B1) is not limited as long as it can react with the compound (A1), and is a halogenated hydrocarbon, an epoxy compound, an amine compound, an alcohol, a ketone, an aldehyde, or a compound having a carboxyl group. Of these, halogenated hydrocarbons and epoxy compounds are preferred. The compound (B1) may react so as to be directly bonded to the pyrazole skeleton or the pyrazolone skeleton, but reacts so as to bind to a substituent (for example, an alkyl group such as a methyl group) on the pyrazole skeleton or the pyrazolone skeleton. May be.
Further, the additive for lubricating oil according to this embodiment may be obtained by a cyclization reaction between hydrazines (A2) and a dione compound (B2). In this case, the dione compound usually has a group corresponding to the R, but the hydrazines (A2) may have a group corresponding to the R.
The above reaction is carried out under a catalyst such as a base catalyst as necessary.

<Lubricating oil composition>
The lubricating oil composition according to one embodiment of the present invention is obtained by blending the lubricating oil additive with the lubricating oil base oil.
The lubricating oil additive is generally 0.01 to 50% by mass, preferably 0.1 to 30% by mass, more preferably 0.1 to 20% by mass, based on the total amount of the lubricating oil composition. Blended.
In the present specification, the “lubricating oil composition comprising a lubricating oil additive” is not only a “lubricating oil composition containing a lubricating oil additive”, as long as the effects thereof are not impaired. , “A lubricating oil composition containing a modified product obtained by modifying the additive or a reaction product obtained by reacting the additive with another additive”.

In addition, in the lubricating oil composition, antioxidants, antiwear agents, ashless dispersants, metal detergents, and viscosity index improvements that are usually blended in lubricating oils are within the range where the effects of lubricating oil additives are achieved. Other additives such as an agent, a fluidity improver, a friction modifier, and an extreme pressure agent may be blended.
Specifically, examples of the ashless dispersant include succinimide and boronated succinimide. Examples of the succinimide compound include a succinimide compound obtained by reacting a succinic anhydride substituted with a high molecular weight alkenyl or alkyl group with a polyalkylene polyamine. Allocation can be further suppressed by using these ashless dispersants in combination.
The lubricating base oil is not particularly limited as long as it is generally used as a base oil for lubricating oil, but preferably has a kinematic viscosity in the range of 1 to 50 mm ² / s at 100 ° C., ² to 20 mm. Those in the range of ² / s are more preferred. The kinematic viscosity of the lubricating base oil is measured using a glass capillary viscometer according to JIS K2283-1983.

Examples of the lubricating base oil include hydrocarbon oils and synthetic oils.
Examples of the mineral oil include paraffinic mineral oil and naphthenic mineral oil. Specific examples include light neutral oil, medium neutral oil, heavy neutral oil, bright stock and the like by solvent refining or hydrogenation refining.
As the synthetic oil, poly α-olefins, polyphenyl ether, alkylbenzene, alkylnaphthalene, ester oil, glycol-based or polyolefin-based synthetic oil, and the like can be used. More specifically, poly-α-olefin, ethylene-α-olefin copolymer, polybutene, alkylbenzene, alkylnaphthalene, polyalkylene glycol, polyphenyl ether, alkyl-substituted diphenyl ether, polyol ester, dibasic acid ester, carbonate ester Silicone oil, fluorinated oil, GTL (Gas to Liquids) and the like can be used.

The lubricating oil composition containing the above additive for lubricating oil is also suitably used as a lubricating oil for internal combustion engines such as gasoline engines and diesel engines, gear oils, bearing oils, transmission oils, shock absorber oils, or industrial lubricating oils. However, it is particularly preferably used for engines.
The apparatus to which the lubricating oil composition is applied includes an internal combustion engine such as a gasoline engine or a diesel engine filled with the lubricating oil composition; a gear structure in which the gears are lubricated with the lubricating oil composition; And a bearing mechanism in which the sliding surface is lubricated with the lubricating oil composition; a transmission filled with the lubricating oil composition; a shock absorber in which a friction part and a sliding surface are lubricated with the lubricating oil composition; Among these, an internal combustion machine such as an engine is preferable.

  EXAMPLES The present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.

The lubricating oil composition was evaluated according to the following method.
[Hot tube test]
The lubricating oil composition was kept flowing at 0.3 ml / hour and air at 10 ml / min for 16 hours in a glass tube having an inner diameter of 2 mm maintained at 270 ° C. The lacquer adhering in the glass tube was compared with the color sample, and a score of 11 levels was given, with 10 points for transparent and 0 points for black. The higher the score, the higher the performance. This test was conducted based on JPI-5S-55-99.
Moreover, the temperature in a glass tube was set to 290 degreeC, and the hot tube test was similarly implemented. [Base number maintenance performance test]
The test oil after the above hot tube test was collected, and the base number was measured by the hydrochloric acid method based on JISK2501. The base number after the test (residual base number) and the base number before the test (initial base number) were compared and expressed as the residual base number rate (%), and the base number maintenance performance was evaluated by the following formula. In addition, it shows that base number maintenance performance is so high that a residual base number rate is high.
Residual base number rate (%) = (residual base number / initial base number) × 100

(Synthesis Example 1)
In a 200 ml four-necked flask, 20.0 g (74.6 mmol) of 3-dodecyl-2,4-pentanedione and 40 ml of methanol were placed. To the solution, 3.5 g (76.1 mmol) of methyl hydrazine was added and heated under reflux for 1 hour. After cooling, water was added, methanol was distilled off, and the resulting solid was filtered. In the above general formula (2-1), Y ¹ , Y ² , and Y ⁴ are all methyl groups, and R is 19.5 g (yield 94.0%) of 4-dodecyl-1,3,5-trimethylpyrazole which is an n-dodecyl group was obtained.

(Synthesis Example 2)
In a 200 ml four-necked flask, 10.0 g (37.3 mmol) of 3-dodecyl-2,4-pentanedione and 40 ml of methanol were placed. The solution was charged with 4.0 g (37.3 mmol) of phenylhydrazine and heated to reflux for 1 hour. After cooling, water was added, methanol was distilled off, and the resulting solid was filtered. In general formula (2-1), Y ¹ was a phenyl group, Y ² and Y ⁴ were a methyl group, and R was an n-dodecyl group. Thus, 11.0 g (yield: 86.7%) of 4-dodecyl-3,5-dimethyl-1-phenylpyrazole was obtained.

(Synthesis Example 3)
In a 200 ml four-necked flask, 5.0 g (29.1 mmol) of 1-phenyl-3,5-dimethylpyrazole and 30 ml of dehydrated THF were placed in a nitrogen atmosphere. The mixed solution was cooled to −20 ° C. or lower, and 19.1 ml (30.6 mmol) of butyl lithium having a concentration of 1.6 mol / L (n-hexane solution) was added so that the solution temperature did not exceed −15 ° C. . After stirring for 30 minutes, the temperature was raised to 5 ° C and then cooled again to -15 ° C.
To this mixed solution, 9.7 g (29.1 mmol) of 1-bromooctadecane was added and stirred for 1 hour. Thereafter, the temperature was returned to room temperature over 30 minutes, and the mixture was further heated to 30 ° C. and stirred for 30 minutes. After completion of the reaction, water was added and extracted with toluene. After washing with ion-exchanged water, toluene is distilled off under reduced pressure. In general formula (2-2), Y ¹ is a phenyl group, Y ³ is a hydrogen atom, Y ⁴ is a methyl group, and R is n-nonadecyl. The group, 3-methyl-5-nonadecyl-1-phenylpyrazole, 12.0 g (yield 97.3%) was obtained.

(Synthesis Example 4)
In a 200 ml four-necked flask, 5.0 g (29.1 mmol) of 1-phenyl-3,5-dimethylpyrazole and 30 ml of dehydrated THF were placed in a nitrogen atmosphere. This solution was cooled to −20 ° C. or lower, and 19.1 ml (30.6 mmol) of butyllithium having a concentration of 1.6 mol / L (n-hexane solution) was added so that the solution temperature did not exceed −15 ° C. After stirring for 30 minutes, the temperature was raised to 5 ° C and then cooled again to -15 ° C.
To this mixed solution, 7.0 g (29.1 mmol) of 1,2-epoxyhexadecane was added and stirred for 1 hour. Thereafter, the temperature was returned to room temperature over 30 minutes, and the mixture was further heated to 30 ° C. and stirred for 30 minutes.
After completion of the reaction, water was added and extracted with n-butanol. After washing with ion-exchanged water, n-butanol is distilled off under reduced pressure. In general formula (2-2), Y ¹ is a phenyl group, Y ³ is a hydrogen atom, Y ⁴ is a methyl group, and R is 3- 11.9 g (yield 99.3%) of 3-methyl-5- (3-hydroxyheptadecyl) -1-phenylpyrazole, which is a hydroxy-n-heptadecyl group, was obtained.

(Synthesis Example 5)
A 200 ml four-necked flask was charged with 16.0 g (59.7 mmol) of 3-dodecyl-2,4-pentanedione, 20 ml of methanol, and 20 ml of toluene. The solution was charged with 3.3 g (65.7 mmol) of hydrazine 1-hydrate and heated to reflux for 1 hour. After cooling, water is added, toluene and methanol are distilled off, and the resulting solid is filtered. In general formula (2-1), Y ¹ is a hydrogen atom, Y ² and Y ⁴ are methyl groups, and R is n. There was obtained 8.1 g (yield 51.4%) of 4-dodecyl-3,5-dimethyl-pyrazole which is a -dodecyl group.

(Synthesis Example 6)
In a 200 ml four-necked flask, 3.2 g (80.2 mmol) of sodium hydride (with 40% mineral oil) was added, and washed with n-hexane to remove the mineral oil. 20 ml of dehydrated THF was added, and a THF solution of 7 g (72.9 mmol) of 3,5-dimethylpyrazole was added dropwise over 30 minutes under a nitrogen stream.
The reaction solution was heated to 50 ° C. and stirred for 30 minutes, and then a THF solution of 17.5 g (72.9 mmol) of 1,2-epoxyhexadecane was added and refluxed for 2 hours. The reaction solution was cooled, water was added, and THF was distilled off under reduced pressure. The produced solid was filtered, and 3,5-dimethyl in general formula (2-3), wherein Y ² and Y ⁴ are a methyl group, Y ³ is a hydrogen atom, and R is a 2-hydroxy-n-hexadecyl group. 24.6 g (yield 100%) of -1- (2-hydroxyhexadecyl) -pyrazole was obtained.

(Synthesis Example 7)
In a 200 ml four-necked flask, 7 g (40.2 mmol) of 1-phenyl-3-methyl-5-pyrazolone, 2.5 g (44.2 mmol) of potassium hydroxide and 20 ml of dimethylacetamide (DMAc) were added, and the mixture was heated to 100 ° C. Heated. The generated water was removed under a nitrogen stream, 13.4 g (40.2 mmol) of DMAc solution of 1-bromooctadecane was added, and the mixture was stirred with heating at 110 ° C. for 4 hours. Thereafter, the reaction solution was cooled, water was added, and the mixture was extracted with toluene. After washing with ion-exchanged water, toluene is distilled off under reduced pressure. In general formula (2-4), Y ¹ is a phenyl group, Y ³ is a hydrogen atom, Y ⁴ is a methyl group, and R is an n-octadecyl group. , 16.8 g (98.1% yield) of 3-methyl-5- (octadecyloxy) -1-phenyl-pyrazole was obtained.

(Synthesis Example 8)
A 200 ml four-necked flask was charged with 2.0 g (50.6 mmol) of sodium hydride (containing 40% mineral oil) and washed with n-hexane to remove the mineral oil. 20 ml of dehydrated DMAc was added, and a DMAc solution of 8 g (46.0 mmol) of 1-phenyl-3-methyl-5-pyrazolone was added dropwise over 30 minutes under a nitrogen stream.
After dropping, the reaction solution was heated to 70 ° C. and stirred for 30 minutes, and then 11.0 g (46.0 mmol) of DMAc solution of 1,2-epoxyhexadecane was added and stirred at 130 ° C. for 5 hours. Thereafter, the reaction solution was cooled, water was added, and the mixture was extracted with n-butanol. After washing with ion-exchanged water, n-butanol was distilled off under reduced pressure. In general formula (2-5), Y ¹ was a phenyl group, Y ⁴ was a methyl group, and R was 2-hydroxy-n-hexadecyl. As a result, 15.3 g (yield: 80.3%) of 4- (2-hydroxyhexadecyl) -3-methyl-1-phenylpyrazolone as a group was obtained.

(Synthesis Example 9)
In a 200 ml four-necked flask, 10.00 g (89.3 mmol) of 1,3-dimethyl-5-pyrazolone, 5.5 g (98.2 mmol) of potassium hydroxide and 20 ml of dimethylacetamide (DMAc) were added, and the mixture was heated to 100 ° C. Heated. The generated water was removed under a stream of nitrogen, 29.67 g (89.3 mmol) of 1-bromooctadecane in DMAc was added, and the mixture was heated and stirred at 110 ° C. for 4 hours. Thereafter, the reaction solution was cooled, water was added, and the mixture was extracted with toluene. After washing with ion-exchanged water, toluene is distilled off under reduced pressure. In general formula (2-4), Y ¹ and Y ⁴ are methyl groups, Y ³ is a hydrogen atom, and R is an n-octadecyl group 9 Got. 32.0 g of 1,3-dimethyl-5- (octadecyloxy) -pyrazole (yield 98.0%) was obtained.

(Synthesis Example 10)
A 200 ml four-necked flask was charged with 5.00 g (51.0 mmol) of 3-methyl-5-pyrazolone, 5.38 g (112.0 mmol) of potassium hydroxide and 30 ml of dimethylacetamide (DMAc) and heated to 100 ° C. . The generated water was removed under a nitrogen stream, 34.01 g (102.0 mmol) of 1-bromooctadecane in DMAc was added, and the mixture was stirred with heating at 110 ° C. for 4 hours. Thereafter, the reaction solution was cooled, water was added, and the mixture was extracted with toluene. After washing with ion-exchanged water, toluene is distilled off under reduced pressure. In general formula (2-6), Y ³ is a hydrogen atom, Y ⁴ is a methyl group, and R is an n-octadecyl group. -5-octadecyloxy-1-octadecyl-pyrazole and 5-methyl-3 in general formula (2-7), wherein Y ³ is a hydrogen atom, Y ² is a methyl group, and R is an n-octadecyl group. 29.8 g (yield 96.9%) of a mixture of -octadecyloxy-1-octadecyl-pyrazole was obtained.

Examples 1-10
Lubricants of Examples 1 to 10 obtained by blending 2 parts by mass of each of the compounds obtained in Synthesis Examples 1 to 10 and 8 parts by mass of boronated succinimide with 90 parts by mass of mineral oil of 50 neutral fraction An oil composition was obtained.
The boronated succinimide was a polybutenyl group having a number average molecular weight of 960, a base number: 29.4 mgKOH / g, and a boron content: 2.0% by mass.

Comparative Example 1
Comparative Example 1 was a lubricating oil composition obtained by blending only 8 parts by mass of boronated succinimide with 92 parts by mass of mineral oil of 50 neutral fraction without blending the compound represented by the general formula (1). Things were used.
Comparative Example 2
Under a nitrogen atmosphere, a 200 ml four-necked flask was charged with 1.4 g (37 mmol) of sodium hydride (40% mineral oil) and 20 ml of dehydrated DMF, and a solution of 2.5 g (37 mmol) of imidazole in 20 ml of dehydrated DMF was added dropwise. Next, 12.6 g (30 mmol) of 2-decyl-1-bromotetradecane dissolved in 15 ml of toluene was added dropwise to the reaction mixture, and the mixture was reacted at 100 ° C. for 7 hours. After the solvent was distilled off, the residue was dissolved in 300 ml of hexane and washed with water. After drying over magnesium sulfate, hexane was distilled off and the residue was purified by silica gel column chromatography to obtain 8.5 g (yield 70%) of 1- (2-decyltetradecyl) imidazole which is the compound of Comparative Example 2.
As in Examples 1 to 10, 2 parts by mass of the compound obtained in Comparative Example 2 and 8 parts by mass of boronated succinimide were mixed with 90 parts by mass of mineral oil for 50 neutral fractions. The lubricating oil composition of Example 2 was obtained.

  When the above Examples and Comparative Examples were evaluated, in Examples 1 to 10, the hot tube test score was higher in a high-temperature environment than in Comparative Examples 1 and 2, and the base number residual ratio was good. It can be understood that the additive for lubricating oil represented by the general formula (1) is a detergent having high basicity maintenance and high temperature stability.

  The additive for lubricating oil of the present invention is an ashless detergent that improves the base number of the lubricating oil and improves the base number maintainability in a high temperature environment of 270 ° C. or higher by blending with the lubricating oil. It can be used.

Claims (11)

An additive for lubricating oil represented by the following general formula (1).

(However, Y < ¹ > -Y < ⁴ > is a hydrogen atom or a substituent each independently, and at least 1 is either R or OR among these, R is a substituted or unsubstituted C10-25 carbon number. It is an aliphatic hydrocarbon group.)   The additive for lubricating oil according to claim 1, wherein R in R or OR is selected from a substituted or unsubstituted alkyl group and a substituted or unsubstituted alkenyl group.   The substituent other than R or OR is a hydrocarbon group having 1 to 9 carbon atoms which may have at least one of a nitrogen atom, an oxygen atom, a sulfur atom and a halogen atom, a substituted or unsubstituted carbon number. The lubricating oil according to claim 1 or 2, which is selected from 1 to 9 hydrocarbon oxy groups, hydrocarbon groups having 6 to 12 carbon atoms containing an aromatic ring, hydroxyl groups, thiol groups, halogen atoms, and amino groups. Additives. The additive for lubricating oil according to any one of claims 1 to 3, wherein at least one of Y ^{1 to} Y ⁴ is an aryl group having 6 to 12 carbon atoms. At least one of Y ¹ to Y ^4, but lubricating oil additive according to any one of claims 1 to 4 is an alkyl group having 1 to 4 carbon atoms. At least one of Y ¹ to Y ^4, but lubricant additive according to claim 1 which is selected from a hydrogen atom and a hydroxyl group. Any one of Y ^{1 to} Y ⁴ is either R or OR, and the other three are each independently an alkyl group having 1 to 4 carbon atoms, a hydrogen atom, a hydroxyl group, and an aryl having 6 to 12 carbon atoms. The additive for lubricating oil according to any one of claims 1 to 6, which is selected from a group. 8. The lubricating oil according to claim 1, wherein at least one of Y ^{1 to} Y ⁴ is selected from a hydroxyalkyl group having 10 to 25 carbon atoms and an alkoxyl group having 10 to 25 carbon atoms. Additive. The additive for lubricating oil according to any one of claims 1 to 8, wherein Y ⁴ is a methyl group. The additive for lubricating oil according to claim 9, wherein Y ² is a methyl group.   The lubricating oil composition formed by mix | blending the additive for lubricating oils of any one of Claims 1-10 with a base oil.